Abstract-A study of the terahertz C-V characteristic of the Schottky barrier diode

Tianhao Ren,  Yong Zhang,

https://ieeexplore.ieee.org/document/8059060/

In this paper, we present a concept called the terahertz C-V characteristic of the Schottky barrier diode, which is different from the conventional C-V characteristics. We have also presented a new equation to precisely describe it. The terahertz C-V characteristic has been carefully examined, first by using the measured capacitances at low frequencies and then by using a 225 GHz tripler. The results show this new concept is rational and necessary in terahertz regions. The agreement between the simulated and measured results of the 225 GHz tripler is improved by using the terahertz C-V characteristic.

Abstract-A micromechanical tunable 3D metamaterial based on periodic rotatable double split resonant rings

Zeng Qu, Yong Zhang, Binzhen Zhang,

https://www.sciencedirect.com/science/article/pii/S0030402618309616

The electromagnetic response of the reported metamaterial is usually fixed, which greatly limits practical applications. Microstructural reconfiguration produces a drastic and dynamic controllability in metamaterials response that typically depend on shape, size, and distribution of metaatoms. Periodic rotatable double split resonant rings (DSRRs) structured on an ultrathin dielectric are adopted to design a micromechanical tunable 3 dimensional metamaterial (MT3DM). The powerful tunability quantified by transmissivity is conveniently achieved by mechanically changing location of gap in inner split ring. Modulation of transmissivity amplitude, resonance frequency, and band width reaches 54.41 dB, 0.31 THz, and 0.08 THz, respectively. The microstructure, equivalent circuit model, and reconfiguration mechanism of the proposed MT3DM are deeply discussed. The adjustable resonance can be easily scaled to the entire spectrum by geometrically regulating. Based on the powerful controllability, the proposed MT3DM can by widely applied in biochemical sensing, function materials, and electromagnetic devices including antenna, switch, absorber, and detector.

Abstract-A flexible metamaterial absorber with four bands and two resonators

• Yong Zhang^a, b, 
• Junping Duan^a, b, 
• Binzhen Zhang^a, b,, 
• Wendong Zhang^a, b, 
• Wanjun Wang^c

• ^a Science and Technology on Electronic Test & Measurement Laboratory, North University of China, Taiyuan, Shanxi, 030051, China
• ^b School of Instrument and Electronics, North University of China, Taiyuan, Shanxi, 030051, China
• ^c Department of Mechanical Engineering, Louisiana State University, Baton Rouge, LA 70803, USA
• 
  

http://www.sciencedirect.com/science/article/pii/S0925838817305030

An efficient approach for achieving more resonance bands with fewer resonators is proposed in this paper. We investigate the theory, design, simulation, fabrication, and performance of a flexible metamaterial perfect absorber (MPA) with two resonators and four resonances located in GHz and THz ranges. The sandwich microstructure of the MPA consists of periodic “回” shaped metal patches on a metasurface, a dielectric of FR4 board on the interlayer, and a continuous copper film on the substrate. The four peaks of absorptivity owing to the coupling effect of the strong LC and surface resonance of the outer ring resonator as well as the strong LC and surface resonance of the inner ring resonator are 93.887%, 99.479%, 98.296%, and 93.035% at 38.165 GHz, 155.48 GHz, 231.71 GHz, and 275.27 GHz, respectively. The influences on absorptivity produced by angles, dimensions, and materials are also studied. The proposed MPA, equipped with strong flexibility, ultrathin thickness, light weight, strong absorption, sparks inspirations in designing the MPA with more resonances and fewer resonators.